Recording electric meter



July 21, 1936. L. A. PA|NE 2,048,618

' RECORDING ELECTRIC METR I Filed Feb. 15, 1952 2 Sheets-Sheet 1 Inaanion Louis Paine,

July 21, 1936. L. A. PAINE RECORDING ELECTRIC METER l 1,932 2Sheets-Sheet 2 Filed Feb.

Waffmefer:

V0 and Amrrreferv fmfenor.

CHIS A of the meter 45 I. The other terminal Patented July 21, 1936UNITED STATES PATENT OFFICE Louis A. Paine,

Toronto, Ontario, Canada, as-

signor to Lincoln Meter Company Inc., Springfield, 111. 7

Application February 15, 1932, Serial No. 593,168

7 Claims.

shifted from that of meter.

, A stillfurther important feature consists in" 20 the novel method ofmounting the thermal ele- 7 ments, whereby adjustment of the recordingelement may be efl'ected in a very simple manner. In the accompanyingdrawings, Figure l is a plan view of a meter constructed in accordance Lwith this invention.

Figure 2 is a side elevational view of the meter taken from the rightside of Figure 1 with the casing enclosing the metering element removed.

I'j'igure 3 is an underside plan view showing the so arrangement of thewiring.

Figure 4 is aperspective detail of the operating element of the meter,part thereof being broken away.

Figure 5 is as a volt meter or ammeter.

Figure 6 is a diagram of thearrangement of the wiring for a watt meter.

In the construction herein shown the transformer I has its primarywindingsconnected by 40 the leads 2 and 3 to the posts 4 and Irespectively.

The secondary coil 8 of the transformer Figure 5 has one lead 6connected to one terminal of the adjustable resistance 1, the otherterminal of c which resistance is connected to the binding post 6 of thetransformer secondary winding is connected with a binding post 9 througha portion of a branch it which branch includes the flexible conductingstrips 20 and 2| and is connected to the binding post It in series withthe meter-operating element It later to be described and as illustrateddiagrammatically in Figure 5. v

A post II is rigidly mounted upon a spur gear I! which has a spindleextension journalled in 55 thebase ll andissecuredbyascrew ll engaging arugged form of structure particuiarly the connecting terminals, fwhereby the function of the device may be readily an ammeter to that ofa voltj a diagram of the wiring for the use I would tend to flex theelement I! to a greater or a spring washer i5 which bears against theunderside of the base to hold the post in adjusted positions.

A spindle 16 is rotatably mounted in the base I! adjacent to the spurgear I! and has mounted thereon a spur pinion ll meshing with the spurgear.

The upper end of the spindle is formed with a slot I! which is adaptedto receive the end of a screw driver by means of which the spindle maybe turned to rotatably adjust the position of the spur gear and post ,Hto set the meter to a zero position, as will hereinafter appear.

The post It is split vertically and between the divided portionsthereof. adjacenttothe bottom are placed the fingers of a thermalelectrical resistance element I! which are electrically insulated fromthe post. This element is formed of a plurality of thin flexiblebi-metallic strips which are connected together in pairs at one end andthe element I! here shown, which is formed of two pairs has the adjacentends l9 and l9 electrically connected together at H.

The other ends of the outside pair of resistance elements are connectedrespectively to the flexible conductor strips or terminals 20 and 2|forming partof the branch lead II of the secondary circuit of thetransformer. The current thus flows in series through the fourflngers orstrips of the resistance element is. These flngers are of bi- -metallicconstruction and the resistance to the flow of current is such as toestablish a temperature within the element causing the same to flex inproportion to the heat generated by the flow of current.

In order to equalize or offset the eifect of changes in ambienttemperature in the atmosphere surrounding the thermal element, whichless degree independent of the electrical influence applied thereto, anelement 22 similar to the element i9 is secured in the post I i inopposite or compensating relation to and extends parallel withtheeIement IS, the ends of the composite elements 22 and I! farthestfrom the post ll being connected together by a member 23, which is hereshown formed of a pair of thinplates of insulating material. These areplaced at either side of the ends of the elements I! and 22 farthestfrom the post I i and are secured thereto .by rivets 24. In this way,the flexing of theelement l9 due to changes in temperature of thesurrounding atmosphere will be opposed by a corresponding secured to theupper end of the pin 25 and extends over the graphic record sheet 28which is rotatably mounted upon the supporting plate 38 carried by theposts 3!. Suitable adjustment of the indicator arm relative to therecord sheet may be effected by rotating the post ll about its axis inthe manner previously defined.

The element I9 is electrically insulated from the post ll, preferably bymeans of a very thin strip [9' of mica or other suitable heat-conductingelectrical insulation medium while the element 22 may be in directmetallic contact so that both the element I9 and the element 22 willhave a substantial heat interchange or thermal contact with the post.

This close thermal association between the elements and the extremelysmall mass of metal and the short length of the heat responsive elementrenders the time period of response to the heating effect of the currentvery short and ensures remarkable efliciency.

The post H with its attached thermal and equalizing elements l9 and 22respectively and the electrical connection between the resistanceelement l9 and the terminals of the branch Ill from the secondary coil Sof the transformer are enclosed within a casing 32 which is held inposition by pins 33 arranged at opposite corners, and a cover 34 isremovably secured on the top of said casing by the screws 35.

The post adjusting'spindle [6 extends through an opening in the cover 34to be readily accessible and by turning same a rotative adjustment ofthe post ll may-be made at any time so that the indicator or recordingarm 28 may be set to any desired initial point relative to the graphicrecord sheet 29.

A slot 36 is formed in the cover through which the upper end of the pin25 extends so that the record arm 28 extends from the top of the casingover the record disc.

The post 9' is connected by a bridge wire 31 to a post 38 mounted on thebase and a link 39 is arranged to bridge the posts 8' and III or 8 andI, as may be desired, said link having a slot at one end and a hookedformation at the other, permitting it to be quickly loosened andreadjusted to connect either set of posts.

The post 8 is connected to the branch lead ID from the transformer andwhen the device is used as an ammeter the post 9 is connected with thepost 38 by means of a shunt 4| and the link 39 is swung to the dottedline position of Figure to connect 9' and ID. The terminals 8 and 38 arethen connected in series with the circuit, the

current of which is to be measured.

When the device is used as a voltmeter the post is connected to the post8 by the link 39 thereby connecting the bi-metallic element IS with thesecondary coil of the transformer, the primary of which is energized bythe line voltage connected to posts 4 and 5. The current flowing throughthe element I8 will be proportional to the voltage applied. The bifllarresistor I which is in series with the element I9 provides a means ofadjusting the current flowing through the ele ment F 9 thereby enablingaccurate calibration.

When it is desired to use the device as 9. watt meter the secondary coilS of the transformer will be connected at its mid-point by a lead 43connected to the post 38 and the mid-point ll of the resistance elementI! will be connected to the post! asisshowninFlgm'e 6.

It will be understood from this description that the resistance elementl9 will flex in one direction as a direct result of the heating effectof the possage of the electric current therethrough.

A portion of the heat generated in the bimetallic resistance I l'will betransmitted to the post ll due to the thermal connection between theseelements and this heat travelling along the post will tend to raise thetemperature of the opposing bi-metallic element 22 so that it will tendto flex in opposition to the element l9 connected therewith. However theelement I8 being the actual heat generator its temperature will beproportionately higher than that of the element 22 due to conduction,and consequently, the greater flexing force of the element I! willovercome the relatively feeble flexing force of the element 22 so thatthe pin and consequently the indicator or recording arm 28 will becarried over the surface of the record sheet a proportional distance.

In this way the movement of the arm 28 represents the diflerence betweenthe flexing forces of the elements l8 and 22 and a positive movement inresponse to the flow of current in element l9 will be obtained while atthe same time rapid or extreme fluctuations will be absent due to theinfluential relation of the elements I8 and 22 to each other.

It will be further evident that due to the masses and dissipatingsurfaces represented by the active elements It! and 20 and the post towhich they are thermally attached, the immediate effect of change ofcurrent is not reflected in the instant movement of the indicator, withthe result that there is a damping out of transient changes in thequantity being measured.

It will be readily appreciated that a meter constructed as hereindescribed is extremely simple to make. It has a wide range of adjustmentand can be readily adapted to operate either as a volt meter, an ammeteror as a watt meter.

What I claim as my invention is':

1. In an electric meter, a post adapted to be rotatably mounted, a pairor bi-metallic members rigidly secured at one end in thermal contactwith said post and exteding in a common direction outwardly from thepost in parallelrelation, the metallic elements of said bi-metallicmembers being arranged in opposed relation, and an insulating memberrigidly connecting the outward ends of said members and adapted forconnection to a recording device.

2. In an electric meter, 2. vertical post, a plurality of loops of thinbi-metallic material adapted to have an electric current circulated inseries therethrough and having their open ends rigidly secured to saidpost with the loops arranged in parallel relation, a plurality ofbi-metallic loops thermally secured in said post in parallel arrangementand in a substantially common plane with the atoresaid'loops, a pair ofstrips of insulating material arranged on opposite sides of andconflning the looped ends of said bi-metalllc strips, rivets extendingthrough said insulating members and through the loops of said strips,and a pin having a feather strip extending therefrom inserted betweensaid insulating strips and rigidly secured therebetween and adapted tohave a markin device mounted thereon.

3. In an electric meter, the combination of a bi-metallic resistanceelement adapted to conduct a flow of electric current and to have arecording means operatively connected therewith, and thermally afiectedmeans having a thermal connection with said bi-metallic resistance andoppositionally connected therewith to influence the same in substantialproportion to the heat conduction therefrom through the thermalconnection and additionally acting to offset changes in ambienttemperature said thermal connection comprising a substantial mass ofmetal acting to dampen out the undesirable instant fluctuations of therecording means due to transient changes in the quantity being measured.

4. In an electric meter, a rigid thermal conductor, a bi-metallicresistance element mounted on said thermal conductor, said element beingthermally connected with and electrically insulated from said rigidthermal conductor and being adapted to conduct a flow of electriccurrent and to have a recording means operatively connected therewith,and thermally aii'ected means influentially connected with saidbi-metallic member at a point spaced from the thermal conductor andthermally secured to said thermal conductor to. be influenced by theheat of conduction from the bi-metallic resistance through said rigidthermal conductor said thermal conductor representing a substantial massof metal to act as an eflicient damping out influence to minimizeinstant fluctuations of the recording means due to transient changes inthe quantity being measured.

5. In an electric meter, 9. divided metal post, a bi-metallic resistanceelement secured in substantially flat strip form at one end between thedivided portions of said post and extending laterally in angularrelation to the post, a bi-metallic element corresponding to theaforesaid element also secured between the divided portions of said postin opposed relation to the resistance element extending beyond the postin the same direction and coupled at its outward end to the outward endof the other element, the outward coupled ends of said bi-metallicmembers being adapted for connection with a recording means.

6. In an electric meter, a metal post, a plurality of metallic loopseach having terminal ends rigidly secured to said post, all of saidloops being extended angularly from said post and disposed edge-to-edgein a substantially common plane with the looped ends disposed wellbeyond the post, the looped end of said members being adapted forconnection to a recording means, certain of said bi-metallic membersbeing electrically inisulated from the post and the others being rigidlythermally secured to said post and operating in an opposed direction tothe other bi-metallic members, and means influentially linking outwardlooped ends of all of said bi-metallic members. togethertooflset changesin ambient temperature, said electrically insulated bi-metallic membersbeing adapted to be heated by the flow of an electric current. 7, Meansas claimed in claim 5 in which said divided metal post comprises a pairof bars between which the ends of the bi-metallic elements are-inserted,clamping screws being provided for drawing said bars into rigid clampingrelation with the inserted bi-metallic members.

I LOUIS A. PAINE.

